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101.
102.
该研究以山东万杰医学院为例,针对目前招生规模越来越大,生源质量不断下滑,大面积学生逃学、厌学、考试成绩不及格的严峻现实,提出有关教学方法、教学内容和考核方式的教学三项改革,这三项改革举措顺应了当前高校教育(特别是民办高校教育)形势的发展趋势。通过改革实践,已初见成效,进一步验证了只有坚定不移地搞好教学三项改革,才能保证和提高教学质量,从而使广大学生及其家长的利益得到充分保障;也只有大张旗鼓地继续搞好教学三项改革,学校才有生存和可持续发展的空间。  相似文献   
103.
BACKGROUND: The low level of response (LR) to alcohol is genetically influenced in both humans and animals, and a low LR is a characteristic of offspring of alcoholics that has been reported to predict alcoholism 10 and 15 years later. The genes that contribute to a low LR have not yet been identified. METHODS: A 12-item questionnaire that measures LR, the Self Rating of the Effects of Alcohol (SRE) instrument, was filled out by 745 individuals from the Collaborative Study on the Genetics of Alcoholism (COGA) for whom genetic material was available. These subjects were genotyped by using 336 markers with an average heterozygosity of 0.74 and an average intermarker distance of 10.5 cM. Both quantitative and qualitative nonparametric, sib-pair analyses were carried out for the SRE measure related to early drinking experiences. RESULTS: Correlations of SRE scores across related individuals were significant and between 0.16 and 0.22 for most values, compared with nonsignificant correlations of 0.03 or less among unrelated individuals. Linkage analyses performed by using the FIRST 5 variables (first five times alcohol is consumed) identified four chromosomal regions with lod scores > or = 2.0 whose maximum was also near a marker. One of these chromosomal regions previously was linked to alcohol dependence in the COGA sample. CONCLUSIONS: These data document the familial nature of a low LR to alcohol as measured by the SRE and suggest several chromosomal regions that might contribute to the phenomenon.  相似文献   
104.
41 patients after surgical correction of the tetralogy of Fall of aged 2-24 years (mean 11.2 y.) were followed for 12-65 months (mean 39.5 m.) for known or suspected dysrhythmias. 24-hour ambulatory ECG and exercise testing demonstrated nonsignificant ventricular ectopy (grade 0-1 according to a modified Lown classification) in 28 patients (group I) and significant (grade 2-5) ventricular dysrhythmias in the remaining 13 patients (group II). There were 2 cases of sudden late death in group II, whereas all patients in group I are alive. The victims of sudden death had no, other serious dysrhythmias and received no antiarrhythmic treatment. Ejection fraction of the functional part of the right ventricle estimated by radionuclide angiocardiography was not different in both groups whereas, global right ventricular ejection fraction differed nearly significantly (group I: 39.6 +/- 8.3%, group II: 31.9 +/- 10.4%, p = 0.052). Thus, a diminished global right ventricular ejection fraction caused by an extensive resection and large patch in the right ventricular outflow tract may be connected with the occurrence of higher grades of ventricular ectopy. These may lead to sudden late death.  相似文献   
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106.
目的 分析氟铝联合染毒小鼠骨代谢标志物的变化,探讨氟铝联合对骨毒性效应的特征和机制.方法 采用2因素3水平析因设计方法将昆明种小鼠分成9组,由氟化钠(NaF,0、50、150mg/L)、氯化铝(AlCl3,0、200、600 mg/L)经饮水染毒,24周后采集血清、尿液,测定血清钙(Ca)、磷(P)、镁(Mg)、碱性磷酸酶(ALP)、骨钙素(BGP)、甲状旁腺激素(PTH)及尿Ca、P.结果 氟铝联合对血清Ca、BGP和尿Ca的影响存在交互作用(F值分别为17.370、4.399、9.448,P<0.01),对血清P、Mg、ALP、PTH和尿P的影响不存在交互作用(F值分别为0.416、0.415、1.921、1.362、1.630,P0.05).高氟组血清Ca[(1.13±0.27)mmoL/L]、BGP[(6.56±5.74)μg/L]比对照组[(1.82±0.37)mmol/L、(23.45±15.40)μg/L]降低(P<0.05),高氟低铝组升高到(1.76±0.36)mmol/L、(10.57±4.28)μg/L,高氟高铝组升高到(2.10±0.51)mmoL/L、(15.73±3.15)μg/L;低氟组尿Ca[(6.24±2.61)mmol/mmol Cr]比对照组[(3.12±2.04)mmol/mmol Cr]升高(P<0.05),与低铝、高铝联合时降低[(0.81±0.44)、(1.23±0.41)mmol/mmol Cr],联合作用与氟单独效应相反.高铝组血清Ca为(1.07±0.68)mmol/L、BGP为(7.21±5.22)μg/L.低氟高铝组升高到(1.47±0.18)mmol/L、(10.98±4.35)μg/L,高氟高铝组升高到(2.10±0.51)mmoL/L、(15.73±3.15)μg/L,联合作用对BGP的影响与铝单独作用随剂量增高的效应趋势相同.结论 本实验条件下,铝拮抗氟对部分骨代谢标志物的作用,氟则促进铝的作用,氟铝联合染毒时骨代谢标志物均降低,联合作用抑制骨形成和骨矿化过程,造成骨代谢紊乱.  相似文献   
107.
Heterogeneity in the clinical symptoms of alcohol abuse was examined in 243 men and 305 women from families of hospitalized alcoholics, who had demonstrated different patterns of inheritance of susceptibility to alcoholism. Discriminant analysis was utilized to identify nine alcoholic symptoms that distinguished male relatives of alcoholic men from those of alcoholic women. Inability to abstain from alcohol, fighting and reckless driving while intoxicated, and alcohol treatment other than Alcoholics Anonymous were more prevalent in families of male probands. Male relatives of female probands experienced later onset of loss of control over drinking associated with benders, and cirrhosis and feelings of guilt. Female relatives of alcoholic men and women showed a marked predominance of the latter (Type 1) features, whereas male relatives had different clinical features, depending on the associated mode of inheritance.  相似文献   
108.
We previously found LOXL4 to be alternatively spliced in an anatomic site-specific manner in tumors involving the serosal cavities. LOXL4 splice variants were predominantly or exclusively expressed in effusion specimens from ovarian and breast carcinoma patients, and were absent in primary carcinomas. In the present study, LOXL4 full-length or splice variants were overexpressed in ES-2 and MDA-MB-231 cells and their invasive and metastatic potential and microRNA expression profile were evaluated. ES-2 cells were further injected into SCID mice ovaries and the extent of tumor progression and metastases formation were compared. We show that both splice variants have a positive effect on the metastatic potential of cells in vitro and on tumor progression in vivo. In contrast, full-length LOXL4 is not pro-metastatic, and may even be considered as a tumor suppressor. In addition, we show that LOXL4 is a possible splicing target of the oncogenic splicing factors SRSF1 and hnRNP A1. In conclusion, our results point to a significant role for LOXL4 alternative splicing in tumor progression.  相似文献   
109.
110.
To develop a generic Open Source MRI perfusion analysis tool for quantitative parameter mapping to be used in a clinical workflow and methods for quality management of perfusion data. We implemented a classic, pixel-by-pixel deconvolution approach to quantify T1-weighted contrast-enhanced dynamic MR imaging (DCE-MRI) perfusion data as an OsiriX plug-in. It features parallel computing capabilities and an automated reporting scheme for quality management. Furthermore, by our implementation design, it could be easily extendable to other perfusion algorithms. Obtained results are saved as DICOM objects and directly added to the patient study. The plug-in was evaluated on ten MR perfusion data sets of the prostate and a calibration data set by comparing obtained parametric maps (plasma flow, volume of distribution, and mean transit time) to a widely used reference implementation in IDL. For all data, parametric maps could be calculated and the plug-in worked correctly and stable. On average, a deviation of 0.032 ± 0.02 ml/100 ml/min for the plasma flow, 0.004 ± 0.0007 ml/100 ml for the volume of distribution, and 0.037 ± 0.03 s for the mean transit time between our implementation and a reference implementation was observed. By using computer hardware with eight CPU cores, calculation time could be reduced by a factor of 2.5. We developed successfully an Open Source OsiriX plug-in for T1-DCE-MRI perfusion analysis in a routine quality managed clinical environment. Using model-free deconvolution, it allows for perfusion analysis in various clinical applications. By our plug-in, information about measured physiological processes can be obtained and transferred into clinical practice.  相似文献   
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